Indanthrene Blue RS has a very important role as an additive. It is used in various uncooked edible products. These include various creams and sweet tasting eatables. Apart from that, it also has a lot of chemical purposes as well. These include reactions with various acids. It is an active substance and can cause skin allergies as well. It is used in medical drugs. However, due to its side effects, a lot of people cannot consume it.